The construction industry is wasteful and creates huge CO2 emissions. But what if new buildings had to be adapted and resused or built only with materials already available?

he wrecking ball has always been the great symbol of urban progress, going hand in hand with dynamite and dust clouds as the politicians’ favourite way of showing they are getting things done. But what if we stopping knocking things down? What if every existing building had to be preserved, adapted and reused, and new buildings could only use what materials were already available? Could we continue to make and remake our cities out of what is already there?

We might have no choice, given the way our voracious urban consumption habits are going. In the UK, the construction industry accounts for 60% of all materials used, while creating a third of all waste and generating 45% of all CO2 emissions in the process. It is a greedy, profligate and polluting monster, gobbling up resources and spitting out the remains in intractable lumps. On our current course, we are set to triple material extraction in 30 years, and triple waste production by 2100. If we stand any chance of averting climate catastrophe, we must start with buildings – and stop conceiving them in the same way we have for centuries... [+]